Contact spring assembly for selectors of the coordinate selector type



United States Patent [72] Inventors Sten Daniel Vigren Mosebacke Torg 16-18, Stockholm; Rolf Albin Zander, Storhagsvagen 28 A, Alvsjo; Per Harry Elias Claesson, Osterhagens Gard, Drevviken, Sweden [21 Appl. No. 690,451 [22] Filed Dec. 14, 1967 [45] Patented Dec. 22, 1970 [32] Priority Aug. 31, 1967 [3 3] Sweden [31 No. 12077/ 1967 54] CONTACT SPRING ASSEMBLY FOR SELECTORS OF THE COORDINATE SELECTOR TYPE 11 Claims, 23 Drawing Figs.

[52] US. Cl... 200/166 [51] lnt.Cl H0lh 1/12 [50] Field of Search 200/ 1 75, 178, 43, 166.1, 166C; 335/159; 29/630B, 622,

[56] References Cited UNITED STATES PATENTS 2,066,491 III 937 Sheatsley 200/178 Primary Examiner-Herman 0. Jones Attorney-Strauch, Nolan, Neale, Nies & Kurz ABSTRACT: A contact spring assembly for a selector of the coordinate selector-type arrangement having contact spring groups of fixed and movable contacts located in parallel planes and distributed over a coordinate field. The coordinate field comprising groups of rows of contact spring groups including interconnecting means for the fixed contacts of one group in the same row and interconnecting means for the movable contacts of another group in a row different from the row of the fixed contacts.

PATENTEDnEc22 I976 SHEET 1 OF 8 Jim INVENTORS STE/V DAN/EL V/GRE/V ROL F ALB/IV Z/M/DER PER HARRY ELIAS CL AESSO/V ATTORNEYS PATENTEUUEBZZIHYB 3,649,845

I SHEET 2 UF 8 m mi //v MENTOR? smv DAN/EL v/a/mv ROLF ALB/IV ZA/VDER PER HARRY ELIAS CL AESSO/V y ATTORNEYS 4 CONTACT SPRINGASSEMBLY FOR SELECTORS OF THE COORDINATE SELECTOR TYPE In selectors of the coordinate selector'type which are extensively used in, for example, telephone exchange switchboards,

springs. The contact spring groups are located in the points of intersection between differently directed rows, such as horizontal rows and vertical columns of a coordinate selector field. The contact spring groups can be selectively actuated by simultaneous energization of electromagnetic circuits belonging to one row and one column of said coordinate selector field, as is well known in the art.

In most cases each contact spring group of a selector of the type indicated in theforegoing is .provided with several makecontactsfeach make-contact comprising one fixed and one movable contact spring. In selectors hitherto known the con-.. tact springs are usually piled'on top on each other with insulatingiwashers between the springs atthe clamping ends thereof and with the other ends of thesprings free to make the desired contact functions.

While the use of coordinate selectors for telephone switchboards has proved to be very successful and has led to simplified circuit diagrams for telephone plants and other telecommunication devices, the coordinate selectors hitherto used have some drawbacks of which the following may be mentioned:

l. The adjustment of the individual contact springs is difficult, because of the fact that the contact springs are piled upon each other in several layers and located close. to each other.

2. The interconnection of the contact springs in the selector is complicated and expensive to make.

3. The assembling of the selectors involves a great deal of manual work and is therefore expensive.

It is an objectof the present invention to provide a contact spring assembly for a selector of the coordinate selector type in which these drawbacks are eliminated and also other advantages are obtained. 1 The invention relates to a contact spring assembly for a selector of the coordinate selector type, said assembly comprising a plurality of contact spring groups, each group having a number of contact springs of one type, such as fixed contact springs, and a number of contact springs of another type, such as movablecontact springs, said contact'spn'ng groups being located in points distributed over a coordinate selector field, said field comprising two groups of rows of such contact spring groups, therows ofsaid two groups being parallel to different coordinateaxis of said field, said assembly further comprising means for interconnecting similarly located contact springs of one of said types and belongingto different contact groups belonging-to one and the same row, extending in one of said directions, and means for interconnecting similarly located movable contact springs of different contact groups belonging to one-and the same row extending in the other of said directions, wherein said means for interconnection contact springs of one of said types comprises connection ribs, said ribs for each row being laterally spaced in a plane which is parallel to the plane wherein said contacts are located but spaced therefrom;

Other advantagesandcharacteristics of the present invention will becomeapparent from the following description in which some distinct embodiments of the invention are described by way of an example, references being made to the accompanying drawings, in which:

FIG. 1 isan end view of a part of'a contact spring assembly according to the invention, saidpart comprising an elongated, mounting rib of insulating material ,which supports several contact groups, the contact springs of said groups being located transversally to said mounting rib,

FIG. 2 is atop view of the part illustrated in FIG. 1,

FIG. 3, 4 and 5 are different projections of the mounting rib used for the part illustrated in FIG. 1,

FIG. 6, 7 and 8 are illustrations of different types of contact spring units for mounting in a mounting rib such as illustrated in FIGS. 3-5,

FIG.,9 is a side elevation of a selector comprising a contact spring assembly according to the present invention,

' FIG. 10 is an end view of said selector,

FIG. 11 is a top elevation of said selector,

FIG. 12 and 13 are a side elevation anda top view, respectively, of a contact spring assembly according to a modified form of the present invention,

FIG. 14 is a top view of a mounting rib for a contact spring assembly according to a more advanced embodiment of the invention, C I

FIG. 15 is anend view of the device'according to FIG. 111 as viewed from the bottom end of FIG 14,.

FIG. 16 is a, transversal cross section through the device lac-- cording to FIG. 14 along-the line XVI-XVI as viewed in the direction of the arrows,

FIG. 17 is a contact spring unitfor rib as illustrated in FIG. 14,

FIG. 18 is an end view of the device illustrated in FIG. 17, FIG. 19 illustrates another contact spring unit, like that iilustrated in FIG. 17, but comprising another type of contact springs, 7 FIG. 20 is an end view of the device according to FIG. 19,

mounting in a mounting FIG. 21 illustrates two contact spring units like that illus- I trated in FIG. 17 but comprising other contact springs,

FIG. 22 is a side elevation of the device illustrated in FIG. 21,

FIG. 23 is an end view of the device according to FIG. 21.

In FIGS. 1-4 there is illustrated a longitudinal insulating rib designated B which may be made from a suitable plastic material such as for example polycarbonate ornylon. The mounting strip B has a generally U-shaped cross section as shown in FIG. 5. In the sides of the ribs there are a number of recesses designatedC-l in FIGS; 3 and 4. In the bottom part of the rib there are a number of rectangular openings designated 35-38 in FIG. 2'. v

The spring assembly according to the invention comprises a plurality of the mounting ribs B,,said mounting ribs being mounted on a plate 19, FIG. 9, in parallel relationship to one another.

Each mounting rib B servesas a support for a plurality of contact spring groups. Said contact spring groups are distributed longitudinally along such mounting rib.

In the embodiment illustrated in FIGS. 1-13 each contact spring group comprises only two make-contacts. Each of such make-contacts comprises two contact springs of different types, viz. one movable spring and one fixed contact spring.

The movable contact springs are designated 1- 8 and they represent together four contact spring groups supported by one and the same mounting rib B. The first contact spring group comprises the movable springs 1 and 2, the second group the springs 3 and 4, the third group the springs 5 and 6, and the fourth contact spring group comprises the movable contact springs 7 and 8. There is, according to the embodiment illustrated, a connection spring clamped together with each movablecontact spring 1- -8 and in electrical contact therewith. Thus, the movable contact spring 1 is associated with the connecting spring 11 the movable contact spring 2 is associated with a connecting spring 12, and so on, to the movable contact spring 8, which is associated with the contact spring 18. The free ends of said connecting springs 11 through 18 are bent upwards as illustrated in FIG. 1 and also in FIG. 9, where one such connecting spring is designated 18.

Each contact spring group comprises: also a fixed contact,

to F IG. 1, for example, 21 is a fixed contact spring, the contact surface of which is cooperating with the contact surface of a movable contact spring 40 (see also FIG. 9). Said movable contact spring 40 is, however, mounted in a mounting rib B which is adjacent to the mounting rib B keeping the spring 21.

Each contact spring has a laterally displaced portion such as for the spring 8 the portion 8 (FIG. 2 and FIG. 6). Said laterally displaced portion has the shape of a projection at one side of each spring and a recess at the other side of said spring. Each such recess and each such projection has slanting sides as shown at 31 in FIG. 2 so that two springs may be placed closed adjacent to each other without any risk for electrical contact between such springs. The springs are kept in place in the U-shaped mounting rib B by means of insulating ribs A, FIG. 1, of which the lowermost one is located on top of the connecting springs 11 to 18 and the uppermost one is located on top of the fixed contact springs 21 .to 28. Further, there is a metal rib A located on top of the uppermost strip A. The whole assembly is kept together by means of rivets 35, said rivets penetrating rectangular apertures in the different ribs A and A and apertures 35 and to 38 in the bottom part of the insulating rib B. The rivets are preferably of rectangular cross section.

The rivets 35 are also utilized to fix each mounting rib B to the base plate 19 (FIG. 9 and FIG. 1). The bottom part, according to FIG. 1, of each rivet is broader than the rest of the rivet so that there are shoulders between 'said bottom part and said rest of the rivets. Those shoulders are abutting against one side of the base plate 19, which is opposite to the side where the mounting ribs B are located. The other end of each rivet 35', which projects from the metal rib A, is riveted, bent or otherwise distorted to lock the rivet in place and to keep the parts, which the rivet penetrates, clamped against each other.

In order to facilitate the production of a contact spring assembly according to the present invention a plurality of contact springs may be punched out together as a unit and connected together by a rib extending transversally to the longitudinal direction ofeach contact spring. Such a unit may then be put in place in a mounting rib B andthe interconnecting rib may be cut away after such mounting has taken place.

Thus, in FIG. 6 there is illustrated, how the moving contact springs 1-8 of FIG. 2 are punched out together as a single unit. The springs 1-8 are connected together by means of a rib designated 61-68. Similarly all connecting ribs 11-18 associated with the movable contact springs 1-8 may be punched out as a unit and connected together with a rib designated 711-718 as illustrated in FIG. 7. Also the fixed contact springs 2'1-28 may be punched out as a single unit. Such a unit is illustrated in FIG. 8. Said unit comprises each of the fixed contact springs 21, 22 and soon to 28 andnterconnecting ribs 828 and 829. Further, there is a central portion between each contact spring, said central portion being designated for different parts thereof 821, 822 and 827. In FIG. 8, said interconnecting ribs 828 and 829 are bent so that their planes are transverse to the plane of the drawing. In FIG. 1 said interconnecting ribs are designated 29 and 30 and such interconnecting means between the fixed contact springs 22, 24, 26 and 28 for the interconnecting rib 29, FIG. 1, or 828, FIG. 8, and between the springs '21, 23, 25, 27 for the interconnecting rib 30, FIG. 1, and 829, FIG. 8. But the central portion 822, 827, FIG. 8, is cut away between each fixed contact spring 21-28 after mounting said springs in the U-shaped member B. It should be noted, that in this embodiment said cutting away must be made before applying the rivets 35 because the central parts 822-827 will cover the apertures 35-38 in which the rivets are to be inserted.

This is a disadvantage which may be avoided by punching out the fixed contact springs 21-26 as two units, one unit comprising the contact springs 21, 23, and 27, said contact springs being interconnected by the interconnecting rib (FIG. 1 and FIG. 2 only) and the other unit comprising the fixed contact springs 22, 24, 26 and 28, said springs being interconnected by the interconnecting rib 29 (FIG. 1 only) which is retained.

The movable contact springs of different contact spring groups should also, in many cases, be interconnected by interconnecting conductors. For this purpose the connecting ribs 11 to 18, FIG. 2, are provided. If said ribs are bent upwards to a level which is over the uppermost part of the contact spring group, said interconnecting may be made by a noninsulated conducting wire which is applied to all connecting springs for similarly located movable contact springs belonging to each group of one column of the selector. A short piece of such a conductor is shown in FIG. 1 and designated 11a. Said conductors extend transversally relative to the mounting ribs B. When all such conductors have been applied properly and provisionally fixed at their ends by means of winding a few turns around the extreme connecting springs in each column, the soldering may take place by dipping the whole surface of the assembly in molten tin.

As will be apparent from FIG. 9-11, a plurality of longitudinal ribs B are mounted on the bottom side of a supporting plate 19 (FIG. 9) so that the movable springs projecting from one of the ribs are cooperating with fixed springs projecting from one of the ribs are cooperating with fixed springs projecting from an adjacent rib. On the other side of the base plate 19 there are magnetic circuits for actuating the movable contact springs. Each circuit comprises an E-shaped magnetic core and an armature and there is an insulating stud or rod connected to the armature and extending downwards through a hole in the base plate 19 to the movable contact springs. Each armature should be connected to two adjacent contact springs in one contact spring group. Thus, there are in the device shown one magnetic circuit for the two movable springs 1 and 2 illustrated in FIG. 2 and another for the springs 3 and 4, a third for the springs 5 and 6 and a fourth for the springs 7 and 8. However, in FIGS. 9-11 there are only three magnetic circuits in each direction shown. This is, of course, only by way of example. Of course it is possible to make selectors with any number of contact spring groups and any number of magnetic circuits for actuating such contact spring groups.

In the embodiment shown, each magnetic circuit is a shuntfield circuit, but of course any type of magnetic circuit may be employed.

According to FIG. 13, there is another type of contact spring assembly which represents a more developed stage of the present invention. In this Contact spring assembly, the movable contact springs are interconnected by connecting ribs such as 8 in FIG. 13, said connecting ribs being integral with all contact springs in one and the same longitudinal row of such contact springs. By this means the connecting spring ribs 11-18 in FIG. 1 and FIG. 2 may be avoided and also the connecting together of such contact ribs by means of interconnecting wires as previously described.

In FIGS. 14-16 there is illustrated a longitudinal mounting rib B of insulating material corresponding to the longitudinal mounting rib B in the embodiment already described. In the embodiment now described, however, each contact spring group supported in said longitudinal mounting rib B comprises five make-contacts instead of two.

In FIGS. 14-26 all parts are illustrated on a greater scale than corresponding parts in FIGS. 1-13.

In FIG. 14 there are three contact spring groups indicated, the lowermost of which is designated a and the next designated b and the uppermost designated c. As will be apparent from FIG. 14, all contact spring groups are laterally spaced in the planes of the different contact springs and the springs in each group are also laterally displaced in their own planes. The contact spring groups a b c are identical to each other and, therefore, in the following only contact spring group a will be described more in detail.

Contact spring group a comprises five movable contact springs designated 101a, 102a, 103a, 104a and 105a. Further the contact spring group a comprises five connecting springs 111a, 112a, 113a, 114a and 115a, respectively. Each of said connecting springs is clamped together with the associated movable contact spring. The free end of each connecting spring is bent upwards as illustrated in FIG. 15, in order to enable interconnecting wires to be applied to each upbent end for interconnecting similarly located movable contact springs belonging to different mounting ribs B. Said interconnecting wires extend transversally to the longitudinal direction of each mounting ribB and they maybe fixed to the end of each connecting spring by means of manual soldering. If, however, the connecting springs 111 through 115 are sufficiently long, such as illustrated by phantom lines in FIG. 15, said interconnecting wires (such as the wire 111w shown in FIG. may be temporarily fixed by bending or winding in each end of such wire and may lay straight through the recesses lllr through 115 r illustrated in FIG. 14. After that all such interconnecting wires have been applied, they may be soldered to the different connecting springs simultaneously by means of dipping the surface of the whole assembly in molten tin.

Accordingto FIG. 14, each contact spring group a, b and 0 comprises also fixed contact springs, said fixed contact springs being designated 121a through 1 25a for the lowermost contact spring group a. Said fixed contact springs are superposed on the movable contact springs and the connecting ribs 111 to .115 but insulated from said springs by means of an insulating rib A illustrated in FIG. 15. The fixed contact springs belonging to different contact spring groups distributed along each insulating mounting rib B, but similarly locatedwithin each of said groups, are interconnected in the longitudinal direction of each mounting rib B by means of contact interconnecting ribs. One of saidinterconnecting ribs 130 is integral with the fixed contact springs which they interconnect, viz. the fixed contact springs 121b and 121C, and said springs project laterally from such interconnecting ribs like the teeth of a comb.

The other interconnecting ribs, viz. the ribs13l, 132, 133 and 134 are integral with connecting springs projecting from such ribs and said connecting springs are clamped together with the different fixed contact springs which they should interconnect. This arrangement will be described more in detail in connection with FIGS. 21 to 23. In FIG. 15, however, it is shown that the interconnecting rib 134 is integral with connecting springs such as the spring 141. Said connecting springs are each clamped together with one of the fixed contact springs, such as for example the fixed contact springs 124a through 1240 in FIG. 14.

In a similar way, the interconnecting rib 131 interconnects the springs 125a through 1251:. The rib 132 interconnects the springs 123a through 1230 and the rib 133 interconnects the springs 1220 to 1226.

Each interconnecting rib with its projecting springs is punched out as a unit from sheet metal. In some cases, two or more such units may be punched out at the same time as an integral unit whereby by a special tool certain parts of such unit should be cut away after mounting the whole unit in order to bring about a separation of the different spring units. An example of this method has been described in connection with FIG. 8.

Each interconnecting rib 130-134 is at the free end thereof provided with a soldering tag or the like such as the soldering tag 130s at the end of the rib 130.

The different interconnecting ribs 130 through 134 are laterally distributed'in a plane .above the plane of the fixed contact springs 121 through 125. The interconnecting rib 130 is slightly inclined upwards from said contact springs just in order to get clear of the movable contact springs, such as the spring 201 illustrated in FIG. 15, whichis fastened in an adjaceht mounting rib but cooperating with the contacts of the fixed contact springs mounted in the insulating rib B illustrated in the FIG. The rest of the connecting ribs, designated 131 through 134, are bent upwards to lie in planes which are perpendicular tothe plane of the contact springs 121 through 1251 '"As illustrated in FIG. 4 there is a further U-shaped member designated BF'in FIG. 15 which-has lateral U-shaped portions whidh enclose the upturned portions of the interconnecting ribs 132 and 133, in order to protect and insulate such interconnecting ribs. Otherwise, there would be a risk for short cir- At the uppermost end of the mounting rib B, as seen in FIG.

14, there are mounted a number of contact spring groups, of which only two are illustrated. As illustrated in FIG. 16, each of such contact spring groups comprises changeover contacts constituted by one movable spring S1, one rather rigid, fixed spring S2 and one resilient spring S3 which in rest position is in contact with the spring S2 but upon movement of the spring S1 towards the spring S3 comes into contact with the latter and leaves its contact with the-spring S2. Said contact spring groups are actuated by a separate magnetic circuit which is actuated at the same time as any one of the magnetic circuits actuating the contact spring groups a, b or c is actuated. The

contact spring groups now described serve as circuit connecting means for various circuit connections in a telephone switchboard as well known'in the art.

In FIGS. 17 and 18 there is illustrated a contact spring unit punched out from sheet metal. This unit comprises the interconnecting rib 130 illustrated in FIG. 14. From the rib 130 project not only the fixed contact springs 121a, 122a and 123a, which the rib interconnects according to FIG. 14, but also all other fixed contact springs. As indicated by the checked areas of the other fixed springs in FIG. 17, said other springs, viz. 1220 to 125a, 1221; to 1251 and 1220 to 1250, are separated from the rib 130, after mounting the whole unit, said separation being made by cutting away the checked portions. Thus, the mounting of all fixed contact springs can be made in one single operation.

Between some springs there are rectangular apertures for allowing the rivets 35 to pass between such springs. I

The contact rib 130 may be extended beyond the spring 125a, and the fixed contact springs belonging to the auxiliary contact spring group (illustrated in FIGS. 14 and 16) may pro- 4 ject from the extension. After the mounting, the extension may be cut away from the rest of the rib 130, and also from the projecting contact springs.

Referring now to FIG. 19 and 20 there is illustrated a longitudinal member 1000 from which allconnecting springs 111-115, for all contact groups mount-ed in the mounting rib B illustrated in FIG. 14, project. The unit shown in FIGS. 19 and 20 is intended to be punched out as a single integral unit from sheet metal and mounted as a single integral unit in the supporting rib B. After assembling, the longitudinal bar 1000, is to be cut away by means of a special tool. By this means,

however, the mounting of the contact springs is very much facilitated. Also, all the movable contact springs 101-105 in each contact spring group shown in FIG. 14 may be produced and mounted in the same way.

As shown in FIG. 19, each spring is provided with a laterally displaced portion such as the portion 111' for the spring 111a. Said portion is located between the sidewalls of the U-shaped mounting rib B, in order to keep the springs in place. As shown, for example between the springs: 112a and 113a, there is a rectangular aperture being cut out partly in the spring 112a and partly in the spring 113a said rectangular aperture being designated 112R. Such rectangular apertures are also provided between the springs 11212 and 113k and 1120 and 1130. These apertures are located to coincide with the apertures 35, 36, 37 in the rib B, which are intended for the rivets by means of which the contact spring assembly is to be kept together as described in connection with FIGS. ll--13. The springs in the spring group now illustrated are lying so close to each other and are of such small dimensions that there would not be place for a rivet to pass between the springs without said apertures 112Ra. As an example of the dimensions of a spring assemblyaccording to this embodiment, it may be mentioned that each spring may have a width of 1,9 mm. and that the pitch between two springs may be 3 mm. In such a case there is only 1,] mm. space between two springs. The widths of the aperture 112Ra may be 1,5 mm. which is sufficient for a rivet, such as the rivet 35 in FIG. 1, to pass through said aperture without making contact with anyone of the adjacent springs.

In FIG. 20, there is illustrated how the unit shown in FIG. 19 could be bent before a mounting and before cutting away of the connecting bar 1000 in order to conform with the desired, final shape of the connection springs.

In FIGS. 21 and 22 there is illustrated how the connecting springs 132 and 133 may be punched out together as two separate units and bent to conform with the desired final shape of such units. The units may then be mounted as integral units in the supporting rib B. As these two units are separated from each other from the beginning, there is no necessity of removing any connecting ribs after mounting such units. In FIG. 22 said units are shown as viewed from the side. FIG. 23 is an end view of the unit shown in FIG. 21.

The mounting rib B according to FIGS. 14 to 16 are intended to be mounted besides each other just as is illustrated for the mounting ribs B in FIG. 9 to form a complete contact spring assembly composed of several mounting ribs and com prising a plurality of contact spring groups. In this case, however, each contact spring group comprises five movable contact springs. Those five movable contact springs are actuated by one and the same armature of a magnetic circuit mounted on the other side of a base plate such as the base plate 19 shown in FIG. 9. Also said magnetic circuits may preferably be of the shuntfield circuit type.

It will be appreciated that a contact spring assembly for a coordinate selector as described in the foregoing is very simple to produce and to a large extent may be produced automatically. In case of movable contact springs with connecting ribs 8' as shown in FIGS. 12 and 13, the mounting of the contact springs should be made simultaneously for a plurality of mounting ribs B located besides each other. In that case, such mounting ribs B should be fixed in a framelike fixture which keeps the mounting ribs in place by engaging such mounting ribs at the end thereof, leaving the top and bottom sides of the mounting ribs free. After assembling the springs and after tightening the rivets which keep the springs in place, the whole assembly should be applied to one side of the base plate 13 and riveted thereto by the projecting rivet ends. Thereafter, the fixture should be removed from the mounting ribs.

Several modifications and variations of the present invention would present themselves to a technician skilled in the art. Such modifications using the principle of the present invention should all be falling within the scope of the appended claims.

We claim:

1. A contact spring assembly for a selector of the coordinate type, comprising: a first plurality of movable contacts and a second plurality of fixed contacts; support structure securing said movable and fixed contacts arranged in a plurality of distinct groups; said contact groups distributed over a coordinate selector field comprising two groups of rows of contact groups; the rows in said two groups extending in different directions and being parallel to different coordinate axes of the field; means for interconnecting similarly located fixed contacts in different contact groups belonging to one of said rows; and means for interconnecting similarly located movable contacts of difierent contact groups belonging to the other of said rows.

2. A contact spring assembly according to claim I, said support structure comprising a plurality of elongated mounting ribs of insulating material, said movable and fixed mounted in said mounting ribs, one rib being common for all contact groups in one of said rows, and wherein said contact interconnecting means comprise ribs of conductive material configured to connect similarly located contacts in different ones of said contact groups, said conductive ribs distributed on both sides of said mounting ribs.

3. A contact spring assembly according to claim 2, wherein there are plural conductive ribs at one side of each mounting rib and including ribs of insulating material located between adjacent conductive ribs connecting the contact groups mounted in each said mounting rib.

4. A contact spring assembly for a selector of the coordinate type, comprising: a first plurality of movable contacts and a second plurality of fixed contacts; support structure securing said movable and fixed contacts arranged in a plurality of distinct groups; said contact groups distributed over a coordinate selector field comprising two sets of rows of contact groups and positioned at selected locations in said field; the rows of said different groups extending in different directions and being parallel to different coordinate axes of the field; and said support structure comprising mounting means at each of the locations at which a contact group is positioned, each said mounting means comprising means supporting a contact of one type at the same location and a contact of the other type from a contact group at an adjacent location.

5. A contact spring assembly according to claim 4, wherein the mounting means for each row in one of said contact groups of rows are integral and form an elongated mounting rib and wherein the movable and fixed contacts of said contact groups extend transversely with respect to the longitudinal axes of said elongated mounting ribs, the movable contacts fixed in one rib extending towards an adjacent rib and cooperating with fixed contacts mounted in said adjacent rib, whereby the cooperating contacts mounted in adjacent ribs belong to the same contact group.

6. A contact spring assembly for a selector of the coordinate type, comprising: a plurality of contact groups, each said group including a first plurality of movable contacts and a second plurality of fixed contacts; support structure securing said movable and fixed contacts at specified positions in a coordinate field having plural rows and columns and including means mounting the contact groups in each said column comprising a rib of insulating material; said insulating rib having a generally U-shaped cross section with said movable and fixed contacts mounted transversely relative to said insulating rib, said movable and fixed contacts supported by the bottom portion of said insulating rib and projecting through recesses in the sides thereof; there being groups of contacts distributed along each insulating rib with each group comprising a plurality of superposed contacts and there being strips of insulating material between adjacent contacts in each of said groups, each said strip being common to all contact groups mounted in each said insulating rib.

7. A contact spring assembly according to claim 6, together with an elongated insulating strip superposed on the uppermost contacts of the groups mounted in each rib, an elongated metallic strip on each said insulating strip, and fasteners maintaining the components of the assembly in assembled relationship.

8. A contact spring assembly according to claim 6, together with a base, means fixing said mounting members to said base, electromagnetic actuators having fixed cores and movable armatures mounted on the opposite side of said base, and movable members extending through said base, one end of each such movable member connected to the armature of one of said electromagnetic actuators and the other end of each such member connected to the movable contacts of one of said contact groups.

9. A contact spring assembly according to claim 6, wherein those fixed contacts in a contact group which perform different functions are spaced longitudinally in the mounting rib in which said contact group is mounted, wherein the corresponding movable contacts are similarly spaced, and wherein said fixed and movable contacts are located in different planes.

10. A contact spring assembly according to claim 6, wherein each of said contacts has a laterally displaced U-shaped portion with slanting sides, said displaced portion located inside the U-shaped mounting member and locking the contact in a predetermined, longitudinal position relative thereto.

means interconnecting one of said pluralities of movable and fixed contacts comprising elongated ribs of a conductive material, said ribs extending lengthwise of said assembly, being integral with and thereby electrically connected to selected ones of said contacts, and said rib being disposed transverse to the contact springs and inclined away from the plane of said connected contact springs.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,549,845 Dated December 22, 1970 Claesson It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3, line 51, "andnterconnecting" should be and interconnecting--.

in place as interconnecting-.

beginning.

Signed and sealed this 6th day of July 1971.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. WILLIAM E. SCHUYLER, JR. Attesting Officer Commissioner of Patents FORM O-i050 (1069) I USCOMM-DC 50311 Inventor( Sten Daniel Vigren, Rolf Albin Zander, Per Harry El Column 3, line 58, Insert before "means" --ribs are remaini:

Column 4, Cancel line 22 and cancel "ing" in line 23, at t' 

